The ones I have seen are usually stamped. Mine were, and the markings are consistent with my other sheet metal stampings, namely my rear quarters, deck lid and doors. Is this the norm? I've not researched it enough to give you a strong enough answer. I've parted many cars and have seen many dates. It's always best to restore what you have found. My experience, the codes/ dates are there. Most often, they are in such poor condition most would overlook them. They depths can vary. I'll post a pic when its not arctic in my garage.

*L* well Steve... in the words of many a youngster... 'You made me look!'... there was one I could get to in my trunk (the one that was loose and which I'd laid in upside down.. helping me understand why I said 'dome down' in an earlier post!!~ and after a little cleaning, I did see a '38'.. can't tell if more was there, but if that's a 'week of the year', then it corresponds very well with my 3rd week of September (69) build week. I guess that will serve as my 'new Camaro information learned today'..

Four of my 6 had no stampings. I have looked through many plates of a guy who parted out 67-69 Camaros and found them both ways. Even observed a few with two small holes and noted they seemed to be found in the trunk area but that was only two cars so might have been just a coincidence. I thought I had in my files that the stampings were never decoded to meaning and was a supplier in house thing but http://www.camaros.org/forum/index.php?topic=7606.0

it seems to make sense that they would be stamped with week of productionl.. and that some would be stamped so lightly as to not be visible, or be very hard to read after 40 yrs...?

It would be interesting to note stampings as "H" sure seems to be the first letter used in many. Looking at stamped plugs some for sure seem to have been roll-marked, meaning a mechanical stamper was used which rolls circular to stamp. Used in high volume stamping! http://www.camaros.org/forum/index.php?topic=2438.0;all

it seems to make sense that they would be stamped with week of productionl.. and that some would be stamped so lightly as to not be visible, or be very hard to read after 40 yrs...?

It would be interesting to note stampings as "H" sure seems to be the first letter used in many. Looking at stamped plugs some for sure seem to have been roll-marked, meaning a mechanical stamper was used which rolls circular to stamp. Used in high volume stamping! http://www.camaros.org/forum/index.php?topic=2438.0;all

I left my plug that was loose, sit in a solvent last night, and took another look today. The stamping on it is 'H 3 6'.. my car was build week 38... (what does the H represent?.. the mfg?)..

Here are my plugs and rear quarters, I'll have to dig up more shots come spring of my deck lid, rear body panel, outer wheel housings, doors, but they are all in the same ball park...28, 29, 30. All my numbers seam to be tight.

I left my plug that was loose, sit in a solvent last night, and took another look today. The stamping on it is 'H 3 6'.. my car was build week 38... (what does the H represent?.. the mfg?)..[/quote]Gary, I believe it was John H mentioned the letter designated the stamping plant it was produced at. George